using Docnet.Core.Models;
using Docnet.Core.Readers;
using Docnet.Core;
using System.Drawing;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
using Docnet.Core.Exceptions;

#region Main Code

if (args.Length == 0)
{
    Console.WriteLine("No PDF specified");
    return 1;
}

Console.WriteLine($"Conversion for {args[0]}");
Console.WriteLine("Using configuration");
Console.WriteLine("\tA4 at 96dpi");
Console.WriteLine();
return ReadPDF(args[0]);

#endregion

#region Functions

int ReadPDF(string path)
{
    string outPath = "";
    try
    {
        outPath = Path.GetFileNameWithoutExtension(path);
        Directory.CreateDirectory(outPath);
    } catch (Exception e)
    {
        Console.Error.WriteLine("Error creating file directory");
        Console.Error.WriteLine(e.Message);
        Console.ReadKey();
        return 2;
    }

    try
    {
        using (IDocReader docReader = DocLib.Instance.GetDocReader(path, new PageDimensions(794, 1122)))
        {
            int pages = docReader.GetPageCount();
            Console.WriteLine($"Converting {pages} pages");

            for (int i = 0; i < pages; i++)
            {
                using (IPageReader pageReader = docReader.GetPageReader(i))
                {
                    byte[] rawBytes = pageReader.GetImage();
                    int width = pageReader.GetPageWidth();
                    int height = pageReader.GetPageHeight();

                    using (Bitmap doc = new Bitmap(width, height, PixelFormat.Format32bppArgb))
                    using (Bitmap bmp = new Bitmap(width, height, PixelFormat.Format32bppArgb))
                    {
                        AddBytes(bmp, rawBytes);

                        Graphics g = Graphics.FromImage(doc);
                        g.FillRegion(Brushes.White, new Region(new Rectangle(0, 0, width, height)));
                        g.DrawImage(bmp, new Point(0, 0));
                        g.Save();

                        if (i == 0)
                        {
                            Bitmap thumb = new Bitmap(doc, new Size(doc.Width / 10, doc.Height / 10));
                            using (MemoryStream stream = new MemoryStream())
                            {
                                //saving and exporting
                                thumb.Save(stream, ImageFormat.Jpeg);
                                Console.WriteLine($"Ouputing tumbnail");
                                File.WriteAllText($"{outPath}\\thumb.bjpg", Convert.ToBase64String(stream.ToArray()));
                            };
                        }

                        using (MemoryStream stream = new MemoryStream())
                        {
                            //saving and exporting
                            doc.Save(stream, ImageFormat.Jpeg);
                            Console.WriteLine($"Ouputing page {i + 1}");
                            File.WriteAllText($"{outPath}\\{i + 1}.bjpg", Convert.ToBase64String(stream.ToArray()));
                        };
                    };
                };
            };
        }
    }
    catch(DocnetLoadDocumentException)
    {
        Console.Error.WriteLine("File is not a PDF");
        Console.ReadKey();
        return 3;
    }

    Console.ReadKey();
    return 0;
}

void AddBytes(Bitmap bmp, byte[] rawBytes)
{
    Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);

    BitmapData bmpData = bmp.LockBits(rect, ImageLockMode.WriteOnly, bmp.PixelFormat);
    nint pNative = bmpData.Scan0;

    Marshal.Copy(rawBytes, 0, pNative, rawBytes.Length);
    bmp.UnlockBits(bmpData);
}

#endregion